Liquid crystal display device is roughly classified into three types which include those of transmissive type allowing image display based on a transmissive mode, those of reflective type allowing image display based on a reflective mode, and those of reflective/transmissive type allowing image display based on both of the transmissive mode and reflective mode, and have been widely disseminated as display devices for notebook-type personal computers, television sets and so forth, by virtue of their thin and light-weight features. In particular, the reflective/transmissive-type liquid crystal display device, which adopts features of the reflective type and transmissive type, and is capable of switching over both modes depending on brightness of environment, has been adopted to various portable electronic appliances, by virtue of its advantage in that it can provides clear display even in dark places, while saving the power consumption.
A basic configuration of the reflective/transmissive-type liquid crystal display device is disclosed, for example, in Patent documents 1 and 2.
The reflective/transmissive-type liquid crystal display device needs a larger number of retardation layers as compared with the reflective-type liquid crystal display device and the transmissive-type liquid crystal display device, and consequently raises non-conformities including increase in the cost, and increase in the thickness of the display cell. In addition, due to performances of retardation plates adopted thereto, including λ/4 plate and λ/2 plate, not satisfied over the entire range of the visible light region, there have been known problems in viewing angle characteristics, such as undesirable coloration, narrow angle of viewing in the transmissive mode, and so forth.
Aiming at expanding the viewing angle for ensuring good contrast in display based on the transmissive mode, there have been proposed methods of using an optical compensation film having a nematic hybrid alignment fixed thereon, for a λ/4 layer in the retardation film on the upper and lower sides of a panel, or on one side of the panel, and have partially been put into practical use. The methods are disclosed in Patent documents 3-6, for example.
Aiming at reducing the number of retardation plates, there has been proposed also a method of disposing a retardation film in the reflective area inside the panel (Patent document 7). For the purpose of improving luminance in the transmissive mode, particularly improving peak luminance, there have been proposed still also methods of similarly disposing a retardation film in a reflective area inside the panel (Patent documents 8-15). For the purpose of similarly improving the peak luminance, there has been proposed still also a method of disposing a retardation film in a transmissive area inside the panel (Patent document 15). However, it has been very difficult for these methods to ensure uniformity in the manufacturing and to reduce scattering of light. It has also been difficult to achieve widening the viewing angle for ensuring good contrast and good efficiency of use of light at the same time in the transmissive mode.    Patent document 1: Japanese Laid-Open Patent Publication No. 2000-29010    Patent document 2: Japanese Laid-Open Patent Publication No. 2000-35570    Patent document 3: Japanese Laid-Open Patent Publication No. 2002-31717    Patent document 4: Japanese Laid-Open Patent Publication No. 2004-157453    Patent document 5: Japanese Laid-Open Patent Publication No. 2005-62672    Patent document 6: Japanese Laid-Open Patent Publication No. 2005-62670    Patent document 7: Japanese Laid-Open Patent Publication No. 2003-322857    Patent document 8: Japanese Laid-Open Patent Publication No. 2004-38205    Patent document 9: Japanese Laid-Open Patent Publication No. 2004-219553    Patent document 10: Japanese Laid-Open Patent Publication No. 2004-226829    Patent document 11: Japanese Laid-Open Patent Publication No. 2004-226830    Patent document 12: Japanese Laid-Open Patent Publication No. 2005-242031    Patent document 13: Japanese Laid-Open Patent Publication No. 2005-283850    Patent document 1:4 Japanese Laid-Open Patent Publication No. 2005-283851    Patent document 15: Japanese Laid-Open Patent Publication No. 2004-145327